Apparatus for preventing condensation on the inside surface of alpha show case window



Aug. 15, 1933.

RNSIDE 1,922,927

DENSATION ON THE G. B. BU APPARATUS FOR PREVENTING CON INSIDE SURFACE OF A OW CASE WINDOW Filed D80. 1950 Aim/ways Patented Aug. 15, 1933 APPARATUS FOR TION ON THE PREVENTING CONDENSA- INSIDE SURFACE OF A SHOW CASE WINDOW George Barnhill Burnside, Broomhill, Glasgow,

Scotland Application December 16,

502,777, and in Great Britain December 18,

7 Claims. (01. 20 -405) This invention refers to show cases for the display of goods, particularly show cases for shops, and comprising a window or windows which or any of which may be an outside window, for instance, a front window of a shop, or the show case may form part of an entrance passage to a shop. Show cases to which this invention refers are of the kind which normally form a closed area, isolated from the general interior of the shop, and in which windows of the ordinary kind are used, thus, vision into the shoe case is through a single sheet of glass, not through sheets of glass with space intervening between the surfaces of the sheets. The invention relates to the provision of improved apparatus for preventing the inside surface of a window of such show cases from becoming obscured by condensation of aqueous vapour from the air.

In regard to this invention it may be useful to explain that aqueous vapour is always present in the atmosphere, the quantity varying with the temperature, but a certain maximum cannot be exceeded at any given temperature. When this maximum is present the atmosphere is saturated. As the maximum increases with the temperature, saturated air, if cooled, will not be able tocontain its full quota of aqueous vapour. Some of this vapour, hitherto invisible, will then be condensed and may become visible as mist and be deposited on cold surfaces in the form of dew. Thus, if condensation takes place on the inside surface of a window of a show case and the fall in temperature be sufficiently extended, the condensation may result in total obscurity of vision, and if the temperature is further reduced, the condensed vapour may become frozen.

According to this invention provision is made for inlet of dried air to the show case andfor outlet to the atmosphere of air therefrom while the show case otherwise forms a closed area, the air being induced from the atmosphere andheated and dried by electric heating means. In one arrangement the drying is effected in the region close to the show case, for example, beneath and close to the floor of the case, and inlet of dried air is made at the floor lever of the show case. Outlet of air from the show case may be at the floor level or in the region of the roof of the case or from both. 'For example, at the floor level outlet of air, relatively to inlet, may be laterally at the sides, say, with inlet at a central position of the floor, outlet maybe at the sides thereof close to or at any distance therefrom within the area of the floor, thus it might be near the sides or 1930, Serial No.

ends, sayopposite sides, or ends, or at both sides and ends.

Apparatus for-use with a show case in accordance with this invention comprises means for inlet from and outlet to the atmosphere of air associated in a single structure applicable for installation with electric heating meansas a complete unit.

Oneform of apparatus according to this invention in which provision is made for inlet of dried air at the base of the show case and outlet also at the base, comprises a head portion of grid character, formed with an inlet or inlets and outlet or outlets, and having a flat surface which may be arranged in the plane of the floor of the show case. For example, inlet may be at a middle area and outlet at side or (and) end areas. Apparatus of this kind may comprise an uptake or uptakes, in one of which electric heat elements are housed, and downtakes at two opposite sides of the uptake or uptakes. Admission of air to the uptake or uptakes may be at a level'appre} ciably below the head and the exit from the down takes may be at a level below the head but ap preciably higher than that of admission, or at the same level as that of admission but preferably arranged sothat issuing air is not directly drawn again into the uptake or uptakes, the exit being, for example, spaced apart from the entrance to the uptake or uptakes. The electric heating means may comprise an electric resistance element enclosed in, and insulated from, a body of material of good heat conducting properties from whose outer surface heat is radiated. An example of apparatus and its application is illustrated in the accompanying drawing, in

Figure 1 is a vertical sectional perspective view.

Figure 2 isan inverted sectional plan.

Figure 3 is an elevation, and Figure 4 is a sectional plan showing in diagram an application of the invention. t

The apparatus, see Figures 1 and 2, comprises an inner tubular member A, which in cross section is circular, an electric heat elementZwithin A, and an outer tubular member B which in cross section is rectangular. The members A and B form an uptake at the top of which is agrid 3, from which at the ends down'takes C C ex; tend. This apparatus is shown applied to a shop show case of which 4 is an outside. window, and' 5 is the floor of, the case. The electric heat element 2 in this example comprises a body having heat radiating fins projecting from its surface and made up of two halves heldtogether with a sov spawnssinuous resistance element clamped between, and

insulated, for example by mica, from them. The body is preferably composed of material having good heat conducting properties.

With this apparatus air passes up uptake partly in A and partly in B, through the grid into the show case and passes 'downwar .ly-from the show case through the grid into, the. downtakes C C 7 Figures 3 and 4 illustrate the front portion of a shop having front outside-wi dowse iand between them an entrance passa w-hicl'i there is a show case F, and at eachside o the passage there is a showcase G. jIfhe walls of the show case F may all be of glass.- Each show case G comprises a front wall 4, which is a front outside window of the shop, passage Ava-11s, fi whichoare passage windows of theshopfand enrdwwail 7 which may be part of the side wall of the shop, and a back wall 8 which may be doors, say of glasspr of wood, to give access tothe showcase "for arr a nging the display of goods. Each ofthe oase o s fi. n m l rform c sedarea a 1m the flpo oiefach case apparatus H, according {to ,thisjnvention, is ,fitted, below thelfloor there is; spaceinfree communication with the atmos he e- I claim:

,1. For use in p eventinga window of a show psefroi'o s plastered b n ens on ace of the windowof 1eous ur, pparatus formed asingle structothe ,js wcasc as complete sing electric heating-means for means, communicating Bi i ,o mo an d y n W th h a osp here, ,IQ- the inlet into the show I cduc d he ated and dried hythe sand communicating withthe V e, for the outlet of air from the show c e, w howoase, exc t ,ior said inlet and otherw senormally a closedarea. Z-E us pre ent a window-o a Sh as. From b c min bs u b oodenoatio uponthe inside surfaoe .oi the window of aqueous repa appa at for a a sin l s ructur a lie o e tothe showcaseasa completeunit and sing electric heating ie'ai a ins w th th atmosphere, ,for inletinto the show case of air induced, heated and dried by the heating means} Q s is th Quie o a m os w i as a d .ao e looru oo i fo me -i 7 inlet and outlet of air, which sho v case, except o said i et nd o t t th rwis no m io imsaolos oareo- Ea us o e eveoiine a w w o a show case from becoming obscured by condensation upon the in ide surface of the window of aoueous vapou pparatus i ormed as a vstfouc- We a i ati n the h w ca o ompl co prisingair uptake means communieating with the atmosphere, electric heat ng 6 16? 'm ents housed therein for inducing, heating and a .down ok mean at tw o o i he uptake m ans and communicating wi h the atmosphe a a hood P rtio o id character io rn ed for passage of air from the up: .1? mo e into the show ca e a d or assa e f oi ee the Sh w oo o' oi h wn mes-e which show po e cept i r comm cai??? wi h ill? d u a and loow a i oth who s und ros o ed e .i- F9 use" i preveoiine' a W nd of a for heating case from becoming obscured by condensation upon the inside surface of the window of aqueous vapour, apparatus formed as a single structure applicable to the show case as a complete unit and comprising air uptake means communicatingwith the atmosphere,1-electrici heating elements housed'therein for inducing, heating and drying .air, air downtake means at two opposite sides of the uptake means and communicating with the atmosphere, and a head portion of grid ,oharacteryiormed ior passageof air from the uptalge-inoaihs into: the show case and for passage of ,air from the show case into the downtake n eans,,. adn i ssionpi air to the uptake means he- ;ing at a level appreciably below the head portion and exit from the downtake means being at a ilevelz-below.the1head;portion, admission and exit :beingiso-arrangeol-as to prevent issuing air from being directly drawn again into the uptake meansythe show case, except for communication .withthe said 1 uptake and downtake, 1 otherwise-norma l ormiha cl r '5 Eo r usejn preventing a window-ofashow ca .f om .beoom os obscur d by condensat on uponnthe inside surface of the window of aqueous vapo nahhumtusformed as a single -,structure app able to the showcase as ,a completeunit' and cpmprising, a,. grid; mounte,d in thehottom of the structure, ,a tubular .casing communicating wit th atmos her an connected :to and ex tending below the grid, ,an electric heating :unit in casing for inducingheatii g -;and drying air, andexhaustflqnduits ,formed ,laterally of the tubular casing, and, communicating :with; said grid and with the atmosphere, the show case, except mmunicati n wi h the tubular casing and x aus onduit ot e wi e no mal y f rmin a closed area. i p

,o For use in preventing a window of a show ca e lirom be omin ob cu e y c n s t ppon the insidesurf ace of the window. of aqueous vapour, apparatus ,formed [as ;a single Lstructure applicable to ,theshowcase ,as complete unit and oomp is n a grid ,Inounted inthe bottom of th oi i ating ure an outer tubular casing communil the;atm sph r -andc c ed oa d lg bfllowthegrid, ,a tubular member with outer casing terminating .below the grid, an lectric heatingunit within the inner tubular member and exhaust conduits formed laterally o the t bu a casi and: communicatin with 5am l the showcase, except for communicatipil w th the tub la ca in an exhau c nduits, otherwise normally forming a closed area. ,7, For in presenting Jawindow of a show case from hQQQmlng obscured by condensation 129 5 th ins osu io e o the indow croqu Qll reo up'ao aratus fQ i-mfid as a single strucl ro appli o'olo o the h w case a a compl 1 11 and o. mor s ns a g id mounted in the .bot-. o o th v iruo lira a u ula casing .communi-' ati w th t e mosph re and havin a flarin upper portion connected to the grid, exhaust conduits tor-med laterally of the flaring portion of the tubular casing and communicating with the grid and with the atmosphere and terminating above the bottom of the casing, and an electric heating unit in said casing for inducing,.heating and drying'air, the show case, except for communication with the tubular casing and exhaust condu ts, otherwise normally forming a closed area.

GE BAR H BURNSIDR- 

